Polycystic Kidney Disease in the Medaka (Oryzias latipes) pc Mutant Caused by a Mutation in the Gli-Similar3 (glis3) Gene
Polycystic Kidney Disease in the Medaka (Oryzias latipes) pc Mutant Caused by a Mutation in the Gli-Similar3 (glis3) Gene
复制标题
DOI：
10.1371/journal.pone.0006299
复制
发表时间：
2009-07-17
期刊：
影响因子：
3.7
通讯作者：
Wakamatsu, Yuko
中科院分区：
文献类型：
--
作者：
Hashimoto, Hisashi;Miyamoto, Rieko;Wakamatsu, Yuko
多囊肾病（PKD）是人类常见的遗传性疾病。最近的研究表明越来越多的纤毛基因参与 PKD 的发病机制。在这项研究中，Gli-similar3 (glis3) 基因被确定为 青鳉 pc 突变体（PKD 模型）的致病基因。在 pc 突变体中，发现转座子插入到 pc/glis3 基因的第四个内含子中，导致 pc/glis3 mRNA 剪接异常，从而产生具有缺陷锌指结构域的推定蛋白截短。 pc/glis3 mRNA 在肾小管、前肾管和中肾管的上皮细胞以及胰腺中表达。反义寡核苷酸介导的 pc/glis3 敲低导致青鳉鱼苗的前肾小管中形成囊肿。尽管在青鳉基因组中发现了另外三个 glis 家族成员 glis1a、glis1b 和 glis2，但没有一个在胚胎或幼虫肾脏中表达。在pc突变体中，前肾的尿流率显着降低，这被认为是肾囊肿形成的直接原因。 pc突变体中肾小管上皮表面的纤毛明显短于野生型，这表明缩短的纤毛导致驱动力降低，进而导致尿流率降低。最重要的是，当在小鼠肾上皮细胞中表达时，EGFP 标记的 pc/glis3 蛋白定位于初级纤毛以及细胞核中，表明 pc/glis3 与纤毛功能之间存在密切联系。与具有 GLIS3 突变的人类患者不同，青鳉 pc 突变体没有表现出任何胰腺表型的症状，例如胰岛素表达受损和/或糖尿病，这表明 pc 突变体可能适合用作人类 GLIS3 患者的肾脏特异性模型。
Polycystic kidney disease (PKD) is a common hereditary disease in humans. Recent studies have shown an increasing number of ciliary genes that are involved in the pathogenesis of PKD. In this study, the Gli-similar3 (glis3) gene was identified as the causal gene of the medaka pc mutant, a model of PKD. In the pc mutant, a transposon was found to be inserted into the fourth intron of the pc/glis3 gene, causing aberrant splicing of the pc/glis3 mRNA and thus a putatively truncated protein with a defective zinc finger domain. pc/glis3 mRNA is expressed in the epithelial cells of the renal tubules and ducts of the pronephros and mesonephros, and also in the pancreas. Antisense oligonucleotide-mediated knockdown of pc/glis3 resulted in cyst formation in the pronephric tubules of medaka fry. Although three other glis family members, glis1a, glis1b and glis2, were found in the medaka genome, none were expressed in the embryonic or larval kidney. In the pc mutant, the urine flow rate in the pronephros was significantly reduced, which was considered to be a direct cause of renal cyst formation. The cilia on the surface of the renal tubular epithelium were significantly shorter in the pc mutant than in wild-type, suggesting that shortened cilia resulted in a decrease in driving force and, in turn, a reduction in urine flow rate. Most importantly, EGFP-tagged pc/glis3 protein localized in primary cilia as well as in the nucleus when expressed in mouse renal epithelial cells, indicating a strong connection between pc/glis3 and ciliary function. Unlike human patients with GLIS3 mutations, the medaka pc mutant shows none of the symptoms of a pancreatic phenotype, such as impaired insulin expression and/or diabetes, suggesting that the pc mutant may be suitable for use as a kidney-specific model for human GLIS3 patients.